The distribution of barium and other elements related to biological productivity has been studied in two Palaeocene sections from the Middle East. In the bathyal Ben Gurion section, Israel, Ba* (= Ba/AI2O3 x 15%) concentrations are low, in the range 0.04% to 0.3% in the lower Palaeocene, and very high, 1%to 2%, throughout most of the upper Palaeocene. In the neritic Gebel Aweina section in Egypt Ba* values are low, < 0.1%, throughout the entire Palaeocene. The Ba* enrichments at Ben Gurion and their correlations with increases in Pz05 and opaline silica, and local and global 6I3C maxima, indicate that upwelling and high productivity were important in this region during the late Palaeocene. The absence of Ba* enrichments in the shallower Gebel Aweina section probably reflects the strong depth dependence of biobarium deposition. In the uppermost Palaeocene, at the level where the global benthic extinction event is registered, Ba* concentrations in the Ben Gurion section increase to anomalous 6%. which suggests that upwelling and possibly wind strengths intensified during this event. The results speak against deep-water formation in this region since downwelling and not upwelling is required. Terra Nova, 9, 95-99, 1997

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Paleocene to early Eocene benthic foraminiferal 15•3C and 15•80 records from southern Tethyan sections at Ben Gurion, Israel (paleodepth 500-700 m), and Gebel Aweina, Egypt (paleodepth 150-200 m), show generally similar trends but 1-3%o more negative values than coeval deep-sea isotopic records. In both Tethyan sections a negative 15•3C excursion of 2.5-3%o marks the benthic extinction event in the latest Paleocene. For at least 1 m.y. after this event, 15•3C values were 1.5-2%o more negative on the shelf than at upper bathyal depths, reflecting a deepening of the oxygen minimum zone, possibly related to an increase or spatial shift in upwelling. Benthic 15•80 records indicate a 2-4øC temperature gradient between the shelf and upper bathyal depths. Temperature-salinity reconstructions suggest that upwelling was a dominant mechanism for surface water formation in this part of the southern Tethys during the late Paleocene.

High-resolution oxygen and carbon isotope records for benthonic and planktonic foraminifera have been established through the early Eocene at DSDP Site 550, Goban Spur in the North Atlantic. Benthonic stable isotopic records from Site 550 (estimated palaeodepth c. 4000 m) represent the first documentation of actual deep water properties during the early Eocene.At Site 550 in the earliest Eocene (end of NP10 Zone), a 0.5%o vertical 5180 (i.e. thermal) gradient between subsurface and bottom water was eliminated, probably reflecting upward displacement of subsurface water by intermediate and deep water. Thereafter vertical isothermal conditions prevailed for the rest of the early Eocene. This is consistent with earlier findings suggesting unusually low vertical and latitudinal temperature gradients in the early Eocene ocean. A comparison of the isotopic records from Site 550 and nearby DSDP Site 401 (palaeodepth 1800 m), reflecting intermediate water properties, confirms the isothermal nature of the water column in the eastern North Atlantic. This is in contrast to earlier findings for the Antarctic region (ODP Sites 689 and 690) in the early Eocene, where supposedly warm bottom waters originating in low latitudes were overlain by cooler intermediate waters originating in high latitudes. Both the oxygen and the carbon isotopic records for Sites 550 and 401 indicate that the eastern North Atlantic region was influenced by a single source of intermediate-to-deep water through most of the early Eocene. The benthonic 5180 and 813C values for Site 550 are generally low compared with coeval sections worldwide, indicating that during most of the early Eocene the North Atlantic was dominated by warm and nutrient-enriched deep water formed in a low latitude region.The earliest stages of the long-term cooling trend, which characterizes the second part of the Paleogene, can be traced by a 2~ decrease in bottom water temperatures across the NPI3-NP14 transition at both Sites 550 and 401.

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